generic deployant clasps most watch shop should have. for those original deployants or in general all parts you can expect to pay a premium
do note the length of the folding clasp itself. the one in your pic looks super long.
while it should be easier to wear and take off due to the larger lobang when unfolded, the size of the clasp look like it may not fit a small wrist(less than 6inch) properly/comfortably.
DIY install i suppose you could use a toothpick to poke the springbars if you are really scared of accidentally scratching the clasp.